5dcp

Structural highlights

Disease

[FLNB_HUMAN] Note=Interaction with FLNA may compensate for dysfunctional FLNA homodimer in the periventricular nodular heterotopia (PVNH) disorder. Defects in FLNB are the cause of atelosteogenesis type 1 (AO1) [MIM:108720]; also known as giant cell chondrodysplasia or spondylohumerofemoral hypoplasia. Atelosteogenesis are lethal short-limb skeletal dysplasias with vertebral abnormalities, disharmonious skeletal maturation, poorly modeled long bones and joint dislocations.^[1] Defects in FLNB are the cause of atelosteogenesis type 3 (AO3) [MIM:108721]. Atelosteogenesis are short-limb lethal skeletal dysplasias with vertebral abnormalities, disharmonious skeletal maturation, poorly modeled long bones and joint dislocations. In AO3 recurrent respiratory insufficiency and/or infections usually result in early death.^[2] Defects in FLNB are the cause of boomerang dysplasia (BOOMD) [MIM:112310]. This is a perinatal lethal osteochondrodysplasia characterized by absence or underossification of the limb bones and vertebre. Boomerang dysplasia is distinguished from atelosteogenesis on the basis of a more severe defect in mineralisation, with complete absence of ossification in some limb elements and vertebral segments.^[3] Defects in FLNB are the cause of Larsen syndrome (LRS) [MIM:150250]. An osteochondrodysplasia characterized by large-joint dislocations and characteristic craniofacial abnormalities. The cardinal features of the condition are dislocations of the hip, knee and elbow joints, with equinovarus or equinovalgus foot deformities. Spatula-shaped fingers, most marked in the thumb, are also present. Craniofacial anomalies include hypertelorism, prominence of the forehead, a depressed nasal bridge, and a flattened midface. Cleft palate and short stature are often associated features. Spinal anomalies include scoliosis and cervical kyphosis. Hearing loss is a well-recognized complication.^{[4] [5]} Defects in FLNB are the cause of spondylocarpotarsal synostosis syndrome (SCT) [MIM:272460]; also known as spondylocarpotarsal syndrome (SCT) or congenital synspondylism or vertebral fusion with carpal coalition or congenital scoliosis with unilateral unsegmented bar. The disorder is characterized by short stature and vertebral, carpal and tarsal fusions.^[6]

Function

[FLNB_HUMAN] Connects cell membrane constituents to the actin cytoskeleton. May promote orthogonal branching of actin filaments and links actin filaments to membrane glycoproteins. Anchors various transmembrane proteins to the actin cytoskeleton. Interaction with FLNA may allow neuroblast migration from the ventricular zone into the cortical plate. Various interactions and localizations of isoforms affect myotube morphology and myogenesis. Isoform 6 accelerates muscle differentiation in vitro.

References

1. ↑ Krakow D, Robertson SP, King LM, Morgan T, Sebald ET, Bertolotto C, Wachsmann-Hogiu S, Acuna D, Shapiro SS, Takafuta T, Aftimos S, Kim CA, Firth H, Steiner CE, Cormier-Daire V, Superti-Furga A, Bonafe L, Graham JM Jr, Grix A, Bacino CA, Allanson J, Bialer MG, Lachman RS, Rimoin DL, Cohn DH. Mutations in the gene encoding filamin B disrupt vertebral segmentation, joint formation and skeletogenesis. Nat Genet. 2004 Apr;36(4):405-10. Epub 2004 Feb 29. PMID:14991055 doi:10.1038/ng1319
2. ↑ Krakow D, Robertson SP, King LM, Morgan T, Sebald ET, Bertolotto C, Wachsmann-Hogiu S, Acuna D, Shapiro SS, Takafuta T, Aftimos S, Kim CA, Firth H, Steiner CE, Cormier-Daire V, Superti-Furga A, Bonafe L, Graham JM Jr, Grix A, Bacino CA, Allanson J, Bialer MG, Lachman RS, Rimoin DL, Cohn DH. Mutations in the gene encoding filamin B disrupt vertebral segmentation, joint formation and skeletogenesis. Nat Genet. 2004 Apr;36(4):405-10. Epub 2004 Feb 29. PMID:14991055 doi:10.1038/ng1319
3. ↑ Bicknell LS, Morgan T, Bonafe L, Wessels MW, Bialer MG, Willems PJ, Cohn DH, Krakow D, Robertson SP. Mutations in FLNB cause boomerang dysplasia. J Med Genet. 2005 Jul;42(7):e43. PMID:15994868 doi:10.1136/jmg.2004.029967
4. ↑ Krakow D, Robertson SP, King LM, Morgan T, Sebald ET, Bertolotto C, Wachsmann-Hogiu S, Acuna D, Shapiro SS, Takafuta T, Aftimos S, Kim CA, Firth H, Steiner CE, Cormier-Daire V, Superti-Furga A, Bonafe L, Graham JM Jr, Grix A, Bacino CA, Allanson J, Bialer MG, Lachman RS, Rimoin DL, Cohn DH. Mutations in the gene encoding filamin B disrupt vertebral segmentation, joint formation and skeletogenesis. Nat Genet. 2004 Apr;36(4):405-10. Epub 2004 Feb 29. PMID:14991055 doi:10.1038/ng1319
5. ↑ Bicknell LS, Farrington-Rock C, Shafeghati Y, Rump P, Alanay Y, Alembik Y, Al-Madani N, Firth H, Karimi-Nejad MH, Kim CA, Leask K, Maisenbacher M, Moran E, Pappas JG, Prontera P, de Ravel T, Fryns JP, Sweeney E, Fryer A, Unger S, Wilson LC, Lachman RS, Rimoin DL, Cohn DH, Krakow D, Robertson SP. A molecular and clinical study of Larsen syndrome caused by mutations in FLNB. J Med Genet. 2007 Feb;44(2):89-98. Epub 2006 Jun 26. PMID:16801345 doi:10.1136/jmg.2006.043687
6. ↑ Krakow D, Robertson SP, King LM, Morgan T, Sebald ET, Bertolotto C, Wachsmann-Hogiu S, Acuna D, Shapiro SS, Takafuta T, Aftimos S, Kim CA, Firth H, Steiner CE, Cormier-Daire V, Superti-Furga A, Bonafe L, Graham JM Jr, Grix A, Bacino CA, Allanson J, Bialer MG, Lachman RS, Rimoin DL, Cohn DH. Mutations in the gene encoding filamin B disrupt vertebral segmentation, joint formation and skeletogenesis. Nat Genet. 2004 Apr;36(4):405-10. Epub 2004 Feb 29. PMID:14991055 doi:10.1038/ng1319